Description
Exhaust GY6 139QMB / 139QMA
Some vehicles are equipped from the factory with two rear shock absorbers. These models usually use an aluminum exhaust. It is typically mounted with 2 clamps on a specific exhaust bracket on the right side of the engine. This bracket usually also serves as the lower mounting point for the second rear shock. For this reason, this exhaust is only suitable for vehicles that are originally equipped with this setup.
A header gasket is not included in the scope of delivery and should be ordered separately. Without homologation!
Attention: Not suitable for models with lambda sensor on the exhaust manifold. (Euro4 /Euro5)
Exhaust scooter, moped, motorcycle
The exhaust has a major influence on the performance of scooters and mopeds. By replacing the original with a tuning exhaust, you can improve the gas flow and increase the engine power.
exhaust parts
- The headpipe or header is the connection between cylinder and exhaust, and an exhaust gasket provides the necessary seal. In street-legal systems, the headpipe is equipped with a legally required restriction. Some people remove this restrictor to increase power.
- The actual exhaust body or expansion chamber is connected to the header pipe. In a classic 2-stroke expansion chamber type exhaust, gas pressure waves are used to improve engine performance.
- At the end there us the silencer or muffler that discharges the exhaust gases and, with the help of damping wool, also reduces the noise generated by the vehicle.
Replacing the exhaust
As a general rule, please check if the exhausts fits BEFORE REMOVING THE RESTRICTOR, otherwise the exhaust cannot be returned.
For 2-stroke engines, various settings and components usually need to be adjusted when the original exhaust is replaced with a tuning version. These changes include:
- Adjusting the carburetor by replacing the main jet.
- Upgrading the clutch or replacing the clutch springs.
- For scooters, it may be necessary to reduce the weight of the variator weights.
Tuning Level: Original
We categorize our products into different performance levels Original, Sport, Racing and High End , so that our customers can choose the right parts for their setup. It is really important to combine parts that belong to the same tuning level, this is especially true for cylinders, crankshafts and exhausts.
Under Original you will find parts whose performance and technical specifications are identical to those of the stock part.